Sound amplifier



3 Sheets-Sheet 1 E. A. LEFEBRE SOUND AMPLIFIER Filed Oct. 15, 1923 ATTOR N EY WITNESS:

E. A. LEFEBRE SOUND AMPLIFIER 1925 3 Sheets-Sheet 2 Filed Oct. 15

ATTORNEY WITNESS:

E. A. LEFEBRE SOUND AMPLIFIER Filed Oct. 15, 1923 3 Sheets-Sheet 3 MGR/E ATTOR N EY Patented Dec, 23, 1924.

EDWARD A. LEFEBRE, 0F LONG ISLAND CITY, NEW YORK.

SOUND AMPLIFIER.

Application filed October 15, 1923. Serial No. 668,641. I

To all whom it may concern:

-Be it known that I, EDWARD A. LEFEBRE, a citizen of the United States, residing at Long Island City, in the county of Queens and State of New York, have invented new and useful Improvements in Sound Amplifiers, of which the following is a spcification.

This invention relates to sound amplifiers designed for use in conjunction with acoustical instruments, and the same is based on the principle of acoustics used in the construction of band stands and the like.

It is the primary object of the present invention to provide a sound amplifier of the above mentioned character, preferably con structed of wood, with the component parts designed and associated in a manner to minimize the cost of manufacture, and thus place the article within the financial reach of all, and at the same time produce a device which will greatly amplify the sound of an ac0usti cal instrument without affecting the clearness and naturalness of the sound.

plication like numerals of reference indicate slmllar parts in'the several views, and wherein:

Figure 1 is a view in elevation of the amplifier constructed in accordance with the present invention.

Figure 2 is a sectional view taken on the line 22 of Figure 1.

Figure 3 is a sectional view taken on the line 33 of Figure 2.'

Figure 4 is a detail view of one of the supporting members for the acoustical instrument.

Figure 5 is a similar view of another supporting member therefor.

Figure 6 is a'view similar to Figure 1 of a modified form.

Figure 7 is a sectional view taken on the line 77 of Figure 6.

Figure 8 is a fragmentary sectional view of another modified form of the invention, illustrating another method of supporting the acoustical instrument.

Figure 9 is a vertical sectional view through another modified form of the invention.

Figure 10 is a sectional view taken on the line 1010 of Figure 9.

The sound amplifier is in the nature of an open cabinet designed to amplify the sound emitted from an acoustical instrument adapted 'to be arranged within the cabinet, and the walls of the cabinet are disposed to unitedly define what I term a sounding board, which reflects the sound upwardly and outwardly of the cabinet. The cabinet includes a base 10 which is preferably triangular. in formation, opposed side walls 11 and 12 respectively, an intermediate wall 13, and a front wall indicated at 14. It will be noted upon inspection of the drawings, that each side wall includes an obliquely disposed edge portion 15, and a straight edge portion 16, the corresponding straight edges 16 of the respective walls being tenoned or interlocked throughout their entire length as at 17 Consequently the side walls are arranged substantially in divergent relation, and the intermediate walls 14 is of substantially V-shaped formation to accommodate itself to the space between the obliquely disposed edges 15 of the side walls. With the parts thus arranged the intermediate wall 13 projects forwardly at an angle with respect to the base 10, and forms a point where the apex of the wall 13 is joined with the side walls 11 and 12. The front wall 14 is arranged in parallelism with the intermediate Wall 13, but terminatin a considerable distance below the upper e go of the cabinetand wholly within the confines of the side walls 11 and 12. All of these walls unitedly define what I term a sounding board which causes the sound to be reflected upwardly and outwardly with the vibration of the acoustical instrument 18 arranged with the compartment defined by the space between said walls.

The acoustical instrument may be supported in any suitable manner within the cabinet, but I preferably make use of a pair of spaced parallel walls 19 and 20 respectively, these walls being of relatively different lengths as clearly shown in Figure 2. These walls are received by grooves 21 formed on the side walls 11 and 12 of the structure. Of course these supporting walls -19 and 20 are inserted within the cabinet from the bottom thereof before the base 10 is placed in position, and after the walls have been inserted in their respective grooves, the base is screwed or otherwise suitably secured in position as shown. The walls 19 and 20 thus repose upon the base 10, which holds the supporting walls in proper position for use. .The confrontin faces of these supporting walls are designe to support the acoustical instrument, the bottom 19 being formed with an annular groove 22, and the wall 20 with a circular recess 23, for thepurpose mentioned. 1

In Figures 6 and 7,1 have illustrated a modified form of the invention, the cabinet itself being of the same construction as hereinabove described, this form of the invention differing from the preferred form in the manner of supporting the acoustical instrument 24. In this form of the invention, the acoustical instrument is arranged between and supported by parallel walls 25 and 26' bottom 26 has secured thereto a tapered block 31 which holds the acoustical instrument p'ositioned between its supporting members. The arrangement of the walls 25, 26 and 29 define a pocket for the reception of the.

acousticalinstrument, which pocket opens at its inner-end, so that the sound emitted from the said instrument findsits way out through this pocket from the open end thereof, and.

is subsequently reflected by the walls of the cabinet upwardly and outwardly, with a resultant amplification and clearness of the sound.

In Figure 8, I have illustrated a further modified form of the invention, herein illus-' tratin another method of supporting the acoustical instrument in the cabinet. A

a fragmentary portion of the cabinet is indicated at 33, as this cabinet is constructed in the same manner as descrlbed in connection with the preferred form of the invention.

The acoustical instrument 34 is supported by the spaced parallel walls 25 and 26 respectively, the wall 35 being provided with a plurality of pins 37 adapted to be received by sockets 38 in .the adjacent end of the acoustical instrument 34. While the amplifier may be constructed from any suitable material, I preferably make the device from wood which is particularly advantageous for therpurpose intended and at the same time reduces the cost of manufacture, so that the device can be sold at a nominal price.

In Figures 9 and 10, I have illustrated another modified form of the invention, wherein the acoustical instrument 39 is supported by the opposed side walls 40 of the cabinet, and a supporting wall 41 which is received by grooves formed in the side Walls 40. This supporting wall 41 is of course inserted in the grooves before the base of the cabinet is arranged in position, the supporting wall 41 reposing upon the base when thecabinet is completed. It will be noted upon inspection of Figure 9 that the position of the supporting wall 41 provides a space between this wall and the apex of the side walls, so that the sound may pass upwardly and outwardly from the cabinet as indicated by the arrows in Figure 9.

While it is believed that from the foregoing description, the nature and advantages of the invention will be readily apparent, I desire to have it understood that I do not limit myself to what is herein shown and described and that such changes may be resorted to when desired as fall within the scope of what is claimed.

Having thus described the invention, I claim:

1. A sound amplifier of the character described comprising a cabinet open at its front and inc uding a base and walls arranged to constitute a sounding board adapted to reflect the sound upwardly and outwardly from the cabinet, and an acoustical instrument support arranged within the cabinet and including spaced parallel walls between which an instrument is arranged, said walls being disposed at an angle with respect to the base.

2. A sound amplifier of the character described, comprising a cabinet open at its front, the walls of said cabinet being arranged to define a sounding board adapted to reflect upwardly and outwardly from the cabinet, and an acoustical instrument support including spaced parallel walls supported on the base at an inclination thereto, and associated with the opposed walls of the cabinet, and means on the confronting faces of said parallel walls for supporting an instrument therebetween.

3. A sound amplifier of the character described, comprising a cabinet open at its front, andincluding a base, walls arranged to unitedly define a sounding board adapted to reflect the sound upwardly and outwardly from the cabinet, an acoustical instrument support including spaced parallel walls reposing upon the base, the opposed walls of the cabinet having grooves receiving said arallel walls, and means on the confronting faces of said walls for supporting an instrument thereon.

4. A sound amplifier of the character described comprising a cabinet open at its front, and including a base, and walls arranged to unitedly adapted to reflect the sound upwardly and outwardly instrument support including spaced parallel walls reposing upon the base and arranged within the cabinet, one of said walls having a depression, and the other of said walls having an annular groove to accommodate the opposed ends of an instrument.

5. A sound amplifier of the character described comprising a cabinet open at its front and including a base, and a plurality of walls arranged to unitedly define a sound- 7 ing board adapted to reflect the sound upwardly and outwardly from the cabinet, an acoustical instrument support including spaced parallel walls arranged within the cabinet and associated with the opposed side walls thereof, one of said parallel walls havdefine a sounding board" from the cabinet; an acoustical ing an annular groove to accommodate one end of the instrument, and means carried by the other wall to hold an instrument positioned between said walls.

6. In a sound amplifier of the character described, a cabinet including a base, 0pposed side walls arranged in divergent relation and having adjacent obliquely disposed edges, an intermediate wall designed to fit between the side walls and arrangedat an angle with relation to the base, a front wall rising from the base in parallelism with the intermediate wall, all of said walls constituting a sound board adapted to reflect the sound upwardly and outwardly from the cabinet, an acoustical instrument support arranged within the cabinet and reposing upon the base.

In testimony whereof I have aflixed my signature.

EDWARD A. LEFEBRE. 

